Controlled swelling of swellable polymers downhole

Patent metadata

Field	Value
Publication number	US-9988873-B2
Application number	US-201415115480-A
Country	US
Kind code	B2
Filing date	Jun 27, 2014
Priority date	Jun 27, 2014
Publication date	Jun 5, 2018
Grant date	Jun 5, 2018

Abstract

A method of using a swellable polymer downhole may include introducing a first treatment fluid comprising a first aqueous fluid, a salt with a multivalent cation, and the swellable polymer into a wellbore penetrating a subterranean formation; placing the swellable polymer in a portion of the subterranean formation; contacting the swellable polymer in the portion of the subterranean formation with a second treatment fluid comprising a second aqueous fluid and at least one selected from the group consisting of a precipitating agent, a chelating agent, and a combination thereof; and swelling the swellable polymer in the portion of the subterranean formation, thereby reducing fluid flow through the portion of the subterranean formation.

First claim

The invention claimed is:

1. A method comprising:
introducing a first treatment fluid comprising a first aqueous fluid, a salt with a multivalent cation, and a swellable polymer into a wellbore penetrating a subterranean formation;
placing the swellable polymer in a portion of the subterranean formation;
introducing into the wellbore a second treatment fluid comprising a second aqueous fluid and at least one selected from the group consisting of a precipitating agent, a chelating agent, and a combination thereof;
contacting the swellable polymer in the portion of the subterranean formation with the second treatment fluid; and
wherein contacting the swellable polymer with the second treatment fluid causes swelling of the swellable polymer in the portion of the subterranean formation, thereby reducing fluid flow through the portion of the subterranean formation.

2. The method of claim 1 , wherein the salt is present in the first treatment fluid in an amount of about 1% to about 40% by weight of the first aqueous fluid.

3. The method of claim 1 , wherein the salt comprises at least one selected from the group consisting of magnesium chloride, magnesium bromide, calcium chloride, calcium bromide, calcium acetate, magnesium acetate, ferrous chloride, ferric chloride, ferrous ammonium sulfate, aluminum sulfate, aluminum chloride, an alum, a zirconium (IV) salt, and any combination thereof.

4. The method of claim 1 , wherein the swellable polymer is present in the first treatment fluid in an amount of about 0.001 pounds per gallon of the first aqueous fluid to about 5 pounds per gallon of the first aqueous fluid.

5. The method of claim 1 , wherein the swellable polymer comprises at least one selected from the group consisting of crosslinked polyacrylamide; crosslinked partially hydrolyzed polyacrylamide; crosslinked polyacrylate; a salt of crosslinked polyacrylate; a salt of crosslinked polyalkacrylate; crosslinked hydrolyzed polyacrylonitrile; a salt of crosslinked carboxyalkyl starch; a salt of crosslinked carboxyalkyl cellulose; a salt of any crosslinked carboxyalkyl polysaccharide; crosslinked copolymers of acrylamide and acrylate monomers; crosslinked starch grafted with acrylonitrile and acrylate monomers; a crosslinked polymer of two or more of allyl sulfonate, 2-acrylamido-2-methyl-1-propanesulfonic acid, 3-allyl oxy-2-hydroxy-1-propane-sulfonic acid, acrylamide, and an acrylic acid monomer; and any combination thereof.

6. The method of claim 1 , wherein the second treatment fluid comprises the precipitating agent and the precipitating agent is present in the second treatment fluid in an amount of about 0.01% to about 1% by weight of the second aqueous fluid.

7. The method of claim 1 , wherein the second treatment fluid comprises the precipitating agent and the precipitating agent comprises at least one selected from the group consisting of a hydroxide, a carbonate, a bicarbonate, a sulfate, a phosphate, an oxalates of an alkali metal salt, an ammonium ion, and any combination thereof.

8. The method of claim 1 , wherein the second treatment fluid comprises the chelating agent and the chelating agent is present in the second treatment fluid in an amount of about 0.01% to about 1% by weight of the second aqueous fluid.

9. The method of claim 1 , wherein the second treatment fluid comprises the chelating agent and the chelating agent comprises at least one selected from the group consisting of an aminopolycarboxylic acid-based chelating agent, an amino methylene phosphonate-based chelating agent, phosphono carboxylic acid, any salt thereof, and any combination thereof.

10. The method of claim 9 , wherein the chelating agent comprises the aminopolycarboxylic acid-based chelating agent and the aminopolycarboxylic acid-based chelating agent comprises at least one selected from the group consisting of ethylene diaminetetraacetic acid, nitrilotriacetic acid, iminodiacetate, pentetic acid, ethylene glycol tetraacetic acid, 1,2-bis(o-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid, 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid), and any combination thereof.

11. The method of claim 9 , wherein the chelating agent comprises the amino methylene phosphonate-based agent and the amino methylene phosphonate-based chelating agent comprises at least one selected from the group consisting of amino tris(methylene phosphonic acid), ethylenediamine tetra(methylene phosphonic acid), tetramethylenediamine tetra(methylene phosphonic acid), hexamethylenediamine tetra(methylene phosphonic acid), 1-hydroxyethylidene-1,1-diphosphonic acid, bis(hexamethylene triamine) penta(methylene phosphonic acid, diethylenetriamine penta(methylene phosphonic acid), and any combination thereof.

12. The method of claim 1 further comprising:
producing hydrocarbons from the subterranean formation.

13. The method of claim 1 further comprising:
introducing a third treatment fluid into the wellbore penetrating the subterranean formation; and
allowing the swellable polymer in the portion of the subterranean formation to divert the third treatment fluid to a second portion of the subterranean formation.

14. The method of claim 1 further comprising:
introducing a sweeping fluid into the subterranean formation; and
allowing the swellable polymer in the portion of the subterranean formation to divert the sweeping fluid to a second portion of the subterranean formation.

15. A method comprising:
introducing a first treatment fluid comprising a first aqueous fluid, a salt with a multivalent cation, and a swellable polymer into a wellbore penetrating a subterranean formation;
placing the swellable polymer in a portion of the subterranean formation;
after placing the swellable polymer in the portion of the subterranean formation, displacing the first aqueous fluid with a second aqueous fluid that comprises one selected from the group consisting of: fresh water, none of the salt with the multivalent cation dissolved therein, and a lower concentration of the salt with the multivalent cation dissolved therein as compared to the first treatment fluid;
after displacing with the second aqueous fluid, introducing into the wellbore a second treatment fluid comprising a third aqueous fluid and at least one selected from the group consisting of a precipitating agent, a chelating agent, and a combination thereof, and contacting the swellable polymer in the portion of the subterranean formation with the second treatment fluid, thereby precipitating, chelating, or both the multivalent cation; to cause swelling of the swellable polymer in the portion of the subterranean formation, thereby reducing fluid flow through the portion of the subterranean formation.

16. The method of claim 15 , wherein the salt is present in the first treatment fluid in an amount of about 1% to about 40% by weight of the first aqueous fluid.

17. The method of claim 15 , wherein the swellable polymer is present in the first treatment fluid in an amount of about 0.001 pounds per gallon of the first aqueous fluid to about 5 pounds per gallon of the first aqueous fluid.

18. The method of claim 15 , wherein the second treatment fluid comprises the precipitating agent and the precipitating agent is present in the second treatment fluid in an amount of about 0.01% to about 1% by weight of the third aqueous fluid.

19. The method of claim 15 , wherein the second treatment fluid comprises the chelating agent and the chelating agent is present in the second treatment fluid in an amount of about 0.01% to about 1% by weight of th

Assignees

• Halliburton Energy Services Inc

Inventors

• Reddy B Raghava

Classifications

• C09K8/508

  macromolecular compounds {(C09K8/512 takes precedence)} · CPC title

• C09K8/426

  for plugging · CPC title

• E21B33/13 Primary

  Methods or devices for cementing, for plugging holes, crevices or the like · CPC title

• C09K8/512

  containing cross-linking agents · CPC title

• C09K8/5083

  obtained by reactions only involving carbon-to-carbon unsaturated bonds · CPC title